Exclusion Criteria: Medication use. Subjects who have used the following medications in the past two months will be excluded from the study: (1) previous use of Nitrogen Mustard, Cyclosporin, Cytotoxin, or Cyclophosphamide; (2) regular use of analgesics such as opioids, (3) regular use of prednisone >10mg of prednisone, (4) psychotropic medications, including selective serotonergic reuptake inhibitors, antidepressants, anxiolytics, hypnotics, sedatives and barbiturates. We will also exclude current smokers because of the known effects of tobacco use on proinflammatory cytokine levels. (Helen, I would suggest to remove this sentence. It is clear from studies that patients are higher risk for susceptibility and increased disease activity with smoking. It may decrease our enrollment.)